Temp gauge flucuates

Chrysler uses a modular plug which all the dash components plug in to. The extreme heat in the summer makes the plastic plug expand and looses it's shape. The male part of the plug is nothing more than a thin plastic strip with copper glued on the strip and it bends in the femal slot to make contact. Over a period of years the femal plug looses its ability to keep good contact. Pull the dash out and use a thin scribe to bend up the contacts in the femal plug then slide it back together.

HarryS

Er...no. That is not the cause of this guy's problem. If it were, his temperature gauge would periodically drop from Normal to Low.

Assuming you properly bled the air from the cooling system, your head gasket is most likely going or gone.

DS

A blown headgasket would cause loss of coolant I believe he stated that the system was full.

I dont have much heat at all coming from the heater. I had the head gasket replaced last year and just recently replaced the thermostat to get more heat.But that didnt help. How would I be sure it is the heater coil causing this

Are you from the "South"?

Larry Behold Beware Believe

You could disconnect the heater hoses from the core and connect them together to form a bypass loop, then drive the car and observe the temperature gauge behavior.

If the car has AC, you could set the controls to recirculate, this should switch the bypass valve in the heater hoses to bypass the core.

I've had positive results doing a chemical back flush on these heater cores when they plug.

You could perform a cylinder leakdown test with the radiator cap off, watch for any bubbles at the radiator fill neck, the bubbles may be small or , you may get a gusher of coolant once compressed air is applied to the cylinder, either indicate a combustion chamber leak. You might get the same results by removing three spark plugs and cranking the engine and watching for bubbles at the fill neck, repeat for the other three cylinders.

Just because the head gasket was replaced last year doesn't mean there isn't still a problem, the job could have been done wrong; a warped cylinder head may have been ignored, the head bolts may have been reused, improper torque procedures may have been used, the surface finish on the head may have been wrong, the gasket may have been damaged upon reassembly or the cylinder head may be cracked.

Thank you Max. I removed the hoses from the coil as you suggested and connected them. Temp gauge never went above normal as I drove it. So now that I know it is the heater coil is it worth replacing and how much would that cost

Assuming you properly bled the air from the cooling system, your head gasket is most likely going or gone.

er no Daniel that is not the cause of this guys problem. If it were. he would be adding coolant, please read the post correctly

Hate to be the bearer of bad news, but it sounds like your head gasket is on its last legs. When I was having early symptoms of head gasket failure, I went through four thermostats in a 1 month period because I thought they were just bad since I was having temperature swings. One way you can lessen the temperature swings is to take the thermostat out and drill a 1/8" hole. Install the thermostat with the hole at the top. This will allow any air from the head gasket to escape allowing the thermostat to open better. However, the head gasket will still need to be replaced

Other ways to confirm a bad head gasket:

1) When the engine is warm and at normal operating temperature after driving for about 15 minutes, park the car, but don't shut the engine off. Open the hood and go to the overflow bottle by the radiator for the engine coolant. Take a good look at the fluid in there. If you see some bubbles, then your head gasket is going bad. When my head gasket started to go, this was the first symptom I had. Also, check for foaming/bubbling in the radiator while the engine is running with the radiator cap. 2) Do you see any clouds of white smoke from the exhaust even after engine is warm? If so, this is caused by coolant being burned in the cylinders. If this is happening, expect to have problems with catalytic converter and O2 sensor later on after getting head gasket repaired. Coolant will poison them. 3) A blown head gasket will cause combustion pressure gases to get into the cooling system. This is most likely the reason why your temperature gauge is swinging. The gases cause the thermostat to stick closed making the engine overheat before it opens. Do you notice coolant puking from the overflow bottle especially after driving for a while? If so, this is from the extra pressure due to leaking combustion. 4) Check your oil for contamination. A blown head gasket, when bad enough, will leak water/coolant into the crankcase. If so, your oil will look like chocolate milk. Also, check under your oil cap for white residue. When water gets into the oil, it can create white goblets under the valve cover. Anyway, if these haven't happened yet, don't wait until your oil becomes chocolate milk before you change the head gasket. If this did indeed happen, though, get it fixed IMMEDIATELY! That stuff will eat up the bearings and bottom end of the engine fairly quickly.

Thats a good way to blow your radiator seams also, not to mention alot of other problems. but the OP stated he had his headgasket replaced. Then posted and e mailed me that it was his heater core. After he bypassed it the problem was gone. He is now in thr process of replacing his heater core. Glenn Beasley Chrysler Tech

Are you SURE you have ALL the air out of the system? Many of the 2.2/2.5 cars were notorious for doing exactly what you describe if they had a bubble of air trapped in the system after a fill/flush.

FWIW- the 2.2/2.5 do sometimes blow head gaskets, but its not NEARLY as common on them as it is on the later 2.0/2.4.